Stamp-mill.



No. 768,844. PATENTED AUG. 30, 1904.

J. CABLE.

STAMP MILL.

APPLIUATION FILED NOV. 26, 1902.

N0 MODEL. 2 BHBETBSHEET 1.

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007m maze No. 768,844. PATENTED AUG. 30, 1904.

Y J. CABLE.

STAMP MILL.

APPLICATION FILED NOV. 26. 1902.

N0 MODEL. 2 SHEETS-SHEET 2.

Patented August 30, 1904:.

PATENT OFTTCE.

JOHN CABLE, OF CHICAGO, ILLINOIS.

STAMP-MILL.

SPECIFICATION forming part of Letters Patent No. 768,844, dated August 30, 1904.

Application filed November 26 1902- Serial No. 132,865. (No model.)

To (LZZ whom it may concern.-

Be it known that I, JOHN CABLE, of Ohicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Stamp-Mills; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to improvements in stamp-mills for pulverizing or comminuting ores, and designed more especially for pulverizingmineral-bearing ores preparatory to subjecting said ores to an extracting process for the purpose of removing the mineral from the ore mass.

The invention consists in the matters here inafter set forth, and more particularly pointed out in the appended claims.

In the drawings, Figure 1 is a front perspective view of a stamp-mill made in accordance with my invention. Fig. 2 is a central vertical section thereof. Fig. 3 is adeta'il showing the cams for giving a to-and-fro motion to the stamps. Figs. 4e and 5 are details showing the means for attaching the stem to a stamp.

As shown in said drawings, AA and A A designate the side and front members of a rectangular frame which supports the operative parts of the stamp-mill. The mortarbed B is supported on a foundation B independent of the frame of the stamp-mill, such foundation being made of the usual or any preferred construction. I

G C designate a plurality of stamps located over and operating in connection with the mortar-bed, and said stamps are provided with upwardly-extending stems C, which are connected with suitable mechanism for actuating said stamps. Preferably the mortar-bed B is provided with a number of dies D equal to the number of stamps, said dies being made of the same width as the stamps and made considerably longer than the stamps to permit the stamps to be moved backwardly and forwardly over the dies while the weight of the stamps is bearing thereon, so as to pulverize or grind the ore to the desired mesh. The dies and the mortar-bed are connected by joints which hold the dies stationary on the bed and prevent the pulverized material from being forced under and raising said dies from the bed. herein shown, said dies are provided on their under surfaces and at their ends with tapered ribs 6, which fit into correspondingly-shaped grooves in the upper faces of the mortar-bed. A fibrous packing 6', made of wood or other suitable material, is interposed betweensaid parts, which upon being subjected to moisture is expanded and produces a tight joint and also prevents the accumulation of pulverized material between the parts which would tend to raise the dies. In order to remove the dies when Worn or broken, the mortar-bed is provided with slots 5*, which intersect the slots which receive said ribs, whereby a wedge-key or like implement may be driven into the slots and engage the ribs to force the dies upwardly.

E E designate the side and end walls, respectively, of the mortar. Between the walls and the stamps arelocated two screensE E The screens are stretched in rigid screenframes and are removably seated in grooves in the walls, whereby said screens may be removed for replacement and cleaning, as desired. The outer screens rest on the surfaces of the outer edges of the dies. The coarser material passes through the inner screens, and that which cannot pass through the outer screens falls back onto the mortar-bed through spaces below the inner screens. .The outer screens are made of a mesh to determine the mesh of the tailings, while the inner screens are made somewhat coarser and serve as fenders to protect the material from Wearing the finer screens. The walls are also set into vertical grooves in the intersecting sides of the mortar, so as to be removable. If it is desired to reduce the screen area, one or more of the screens may be removed and the adjacent wall or Walls set into the place or places thereof.

The stamps B are associated with suitable actuating mechanism, which serves to raise the stamps to permit them to drop by gravity upon the material on the dies at one end of the dies and to force each of said stamps while in contact with said material to the other ends of the dies and thence back to the end upon which they dropped, whereby said stamps have a complete to-andfro rubbing action against said material between each drop and rise of the stamp. The coacting faces of the dies and stamps are curved, so that the said stamps and the dies have fixed relation with respect to each other throughout their coacting surfaces during the entire to-and-fro travel of the stamps, whereby an eflicient rubbing or grinding action of the stamps on the dies is at all times insured. Said dies are further provided at their front and rear ends with raised portions or flanges 7/ which act as stops to assist in stopping the to-and-fro motion of the stamps, and thereby relieve the actuating mechanism of this work. So far as the grinding operation is concerned one die may be employed for all the stamps; but I prefer to use one die for each stamp, as it permits amore economical replacement or repair of the dies in case of un equal wear of the dies or parts of the die, it being obvious that in case of breakage of one of the dies or more rapid wear than the other such broken or worn die may be replaced without disturbance to the other dies.

The mechanism for operating said stamps in the manner hereinbefore described is made as follows:

FF designate two side members, and F a top cross member, of a frame which is supported on its lower end on the side bars on the horizontal frame before described. Extending between and connected with said side members F and said horizontal frame are two oblique brace members G, which are bolted at their upper and lower ends to the vertical and horizontal frame members. Attached to the top transverse member F ofthe vertical frame are a plurality of forwardly-extending arms H, and said arms extend through slots in the stai'np-sten'is C and are provided with crosspins having rollers 71/, which engage longitudinal slots 0 in the sides of the stamp-stems, whereby said arms and rollers serve as guides for the rising-and-falling movement of the stamp-stems. As herein shown, each stampstem is made of two laterally separated bars 0' c, which are joined at their upper ends by filling-pieces 0 which are interposed between the bars 0 and attached thereto by rivets or bolts extending through said parts. The slots in the stems 0 therefore which receive the arms H are formed between the side members 0 of said bars. The two bars of each stem enter sockets in the upper face of the stamp, so that said stamp forms a rigid connection between the lower ends of said bars. Preferably the lower ends of said bars are tapered, and the sockets are correspondingly tapered to securely hold the parts together, as shown in Figs. 4: and

I designates a rotative shaft which is supported in bearings f near the upper end of the forward faces of the vertical frame members F, and said shaft is provided with a plurality of cams 1 for operating the stamps. The arms of said cams are adapted in the retation thereof to engage rollers C, mounted on pins extending transversely through and betweenthe side members of the stems. Said cams I are the stamp-lifting cams, and by reason of the location of the rollers between the side members of the stems the cams exert a lifting force on said stems at the central lifting line of the stamps and stems.

J and K designate two rotative horizontal shafts, which are rotatively mounted in bearings g r respectively, on the upper and lower sides of the brace members G of the frame. LLdesignatehorizontally-reciprocatorybars, which extend at their forward ends between the side members of the stem and are pivoted. thereto by means of transverse pins 0, and said. bars extend at their rear ends between the shafts J K before referred to. Said shafts J K are provided with cams J K, which are adapted to engage rollers Z Z, mounted on pins projecting laterally from the bars L, one roller of each bar extending in one direction and the other in the other direction. There are a number of cam-arms J K on each shaft J and K equal to the number of bars L, and each bar is adapted to be operated to force its stamp to and fro on the mortar-bed by two of the cams, the upper cam acting on the upper roller Z to force the bar and connected stamp forwardly, as indicated in Fig. 2, while the lower cam is adapted to strike the lower roller Z of said bar and draw the stamp backwardly. As herein shown, the shaftI is provided with two cams for each stamp-stem, so that its stamp is lifted. twice during each rotation of the shaft, while the shafts J and K are each provided with one cam-arm for each bar L. The shafts I and J K are so timed that the latter rotate with twice the speed of the former, whereby time is given between each drop and lift of the stamps to move the stamps backwardl y and forwardly. The shaft I is provided with a sprocket-wheel 1*, which is connected by a link belt I with a sprocketwheel J on the shaft J, whereby motion of one of said shafts is communicated to the other in a predetermined timed relation. Other sprocket-wheels J K are aflixed to the shafts J and K, respectively, and a link belt J" is trained over said sprocketwheels. Power may be applied to the said machine through either of the shafts 1 or J K; but such application of power is not herein illustrated.

The stamps are made each of an upper and lower part 0 a, respectively, the latter con stituting the shoe of the stamp. Said parts have interfering connection whereby the shoe may be removed from the stamp. The stamp may be made of cast-iron, while the shoe is made of cast-steel. Said shoe is provided with a central projection c", which is tapered and adapted to enter a correspondmgly-tapered socket in the'lower face of the stamp; Said socket is made somewhat larger, however, than said projection, and between the walls of the socket and the projection is interposed a body 0 of fibrous material, such as a soft wood, which upon expansion affords a tight joint between said parts and produces an efficient connection. The parts may be separated in they same manner as the dies are lifted from the mortar-bed.

The backward-and-forward motion of the stamp in conjunction with the dropping motion thereof is of considerable importance, as it effects a more complete pulverizing of the ore than in the case wherethe stamp is merely dropped with a whirling motion, as heretofore common. Not only is the ore pulverized more finely, but the backward-and-forward motion of the stamp on the shoe acts to clear the stamp and shoe of the mixture of ore and water which would tend to adhere thereto if the stamp merely dropped upon the mortar- 'amount of ore may be treated in a given time than with stamps having merely a reciprocating motion. A further advantage of the rubbing or grinding action of the stamps on the bed is that such action serves -to scour and clean the mineral, so that the mineral will be more readily taken up by the amalgam plates and quicksilver. Another advantage of the grinding action is that it disintegrates the ore, so that it may be readly taken up by the water, which is agitated by the backward-andforward motion of the stamps and discharged through the screens before it becomes so finely pulverized that it forms when mixed with the water a thick or muddy consistency, which produces what is termed slime and in which condition the fine mineral is prevented from settling to the amalgam plates while passing over said plates.

The construction whereby the stamps are given a complete to-and-fro movement between the drop and rise thereof is of considerable importance, for the reason that the material which is not crushed or ground during the forward movement of the stamp is in a condition or state to be effectively acted upon during the return movement of the stamp that is to say, when the stamps drop upon a layer of material of a given thickness and are moved forward across the mortar they act to crush or grind a portion of the materialof said layer and reduce the thickness of the layer, so that when the stamps are returned they act upon a thinner layer than in their outward throw. The stamps are moved backwardly and forwardly very rapidly, so that after the stamps are moved forwardly in their outer throw they are returned or drawn rearwardly before the material in the mortar or which is fed thereinto fills in over the paths of the stamps, so that during the return movement of the stamps they act upon a thinner layer of material than during their forward movement, as before stated. The thinner layer is thus acted-upon more effectively during the return movement of the stamps and is more finely crushed or ground than if the stamps be lifted and dropped'between the outward and inward throw thereof. In the latter event time would be given during the period of the rise anddrop of the stamp whileat the outward limit of their throw for the material to fill in behind the stamp, so that in their return movement they would act upon as thick a layer of the material as during their outthrow.

Many changes in the structural details may be made without departing from the spirit of my invention, and I do not wish to be limited thereto, except as hereinafter made the subject of specific claims. It is to be further understood that the combination set forth in each of the several claims is intended to be separately covered without restriction to the combination in which they are found.

I claim as my invention 1. A stamp-mill comprising a mortar-bed, a gravity-acting stamp, means for lifting the stamp from one side of the bed only and releasing the stamp, whereby it drops by gravity upon the material on the mortar-bed, and means for shifting the stamp while bearing on such material from the side of the bed at which it drops to the opposite side of the bed and for returning it, whereby the stamp is shifted in a complete to-and-fro traverse in contact with such material between each drop and lift thereof.

2. A stamp-mill comprising a mortar-bed, a gravity-acting stamp, means for lifting the stamp from one side of the bed only, two cams acting on the stamp after it has been dropped, means whereby one of said cams acts to shift the stamp from the side of the bed at which it dropped to the other side and means whereby the other cam acts to return the stamp while resting on the material on the bed,

whereby such cams effect a complete to-andfro traverse of the stamp between each drop and lift thereof.

3. A stamp-mill comprising a mortar-bed,

a stamp, a stem affixed to said stamp, a lifting-cam acting on said stem to lift the stamp, a horizontally-reciprocatory bar pivoted at its forward end to said stem, and two cams acting on the rear end of said bar after the stamp drops for effecting a to-and-fro movement of the stamp in the mortar.

4:. A stamp-mill comprising a mortar-bed, a plurality of stamps, a plurality of stems attached to said stamps, lifting-cams adapted to act on said stems to severally lift said stamps,

a series of horizontallyreciprocatory bars pivoted at their forward ends to the several stamp-stems, two shafts, one located above said series of pivoted bars and one below the same, and cams on said shafts adapted to act on said bars to effect a toandfro movement of the stamps in the mortar.

5. A stamp-mill comprising a mortar-bed, a stamp, a die on said mortar-bed againstwhich said stamp acts, means for effecting a to-andfro grinding movement of the stamp on the die, said die being provided on its under surface near its margins with ribs or lugs and the mortar-bed being provided .with corresponding slots or mortises and a fibrous packing interposed between said ribs or lugs and slots to hold said die in place.

6. A stamp-mill comprising a mortar-bed, a die in said mortar-bed, a stamp coacting 

